ASTM L7M Custom Bolts

ASTM A320 Grade L7M bolting is designned for low temperature sour gas service where there is high concertration of Hydrogen Sulfide gases present in prodcution situation. Per the specification at Sigma Fasteners we have our own heat treating furnace and hardness testing equipmet for onsite L7M modification and hardness testing. All L7M bolts require 100% hardness testing and at Sigma we keep it in house for complete control over the quality your products demand.